#include <stdio.h>
#define M 3

int display_week(int year,int month,int day)
{
	int w = 0;
	if(month<3)	
	{
		year--;
		month = month +12;
	}
	//printf("------\n%d %d %d\n------\n", year, month, day);
	w = day + 2*month + 3*(month+1)/5 + year + year/4 - year/100 + year/400 +1;
	w = w % 7;
	//printf("w:%d\n", w);
	
	//printf("this is the %d day in this week!\n",w);
	
	return w;
}
